Energy saving roof

ABSTRACT

A roof comprises shingles of asphalt construction and has a color changing outer surface. The color changing outer surface can have a first color under a first environmental condition and a second color under a second environmental condition. The color changing outer surface is capable of both changing from the first color to the second color and from the second color to the first color.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of patent application Ser.No. 12/660,814 filed Mar. 4, 2010.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not Applicable

FIELD OF THE INVENTION

This invention relates to a roof or surface that changes hue whenexposed to varying temperatures and/or light intensities.

BACKGROUND OF THE INVENTION

A traditional building's roof is often exposed to more sunlight than anyother portion of the building. In cooler climates or during the wintermonths this may be considered beneficial as the solar energy absorbed bya roof can provide some amount of desired heating to the building. Moreoften than not this desirable heating during colder months is outweighedby the undesirable heating that occurs in the summer months when thesun's rays are more intense and are extant over a longer portion of a 24hr period than in the cooler months. The energy costs to cool downbuildings could be greatly lessened in some instances if the heatgenerated by a dark roof during the warmer months could be diminished. Aroof that changes from a darker hue/color in cooler weather to a lighterhue/color in warmer weather would be desirable in that a darker roof incooler weather could increase the temperature of the structure, thuslowering energy costs. Energy conservation is of great importance as itreduces the amount of fossil fuels used and lessens dependence onimported oil while at the same time lowering energy costs. There is aneed for a roof that lowers energy usage and costs as the seasonschange.

The instant invention as disclosed within this application, provides aroof system that fills this need. The art referred to and/or describedwithin this application is not intended to constitute an admission thatany patent, publication or other information referred to herein is“prior art” with respect to this invention. In addition, this sectionshould not be construed to mean that a search has been made or that noother pertinent information as defined in 37 C.F.R. §1.56(a) exists.

All US patents and applications and all other published documentsmentioned anywhere in this application are incorporated herein byreference in their entirety.

Without limiting the scope of the invention a brief summary of some ofthe claimed embodiments of the invention is set forth below. Additionaldetails of the summarized embodiments of the invention and/or additionalembodiments of the invention may be found in the Detailed Description ofthe Invention below.

A brief abstract of the technical disclosure in the specification isprovided as well only for the purposes of complying with 37 C.F.R. 1.72.The abstract is not intended to be used for interpreting the scope ofthe claims.

BRIEF SUMMARY OF THE INVENTION

In at least one embodiment of the invention, a roof comprises shinglesof asphalt construction and having a color changing outer surface. Thecolor changing outer surface can have a first color under a firstenvironmental condition and a second color under a second environmentalcondition. The color changing outer surface can be capable of bothchanging from the first color to the second color and from the secondcolor to the first color.

In at least one embodiment, the color changing outer surface includes(a) one or more electron-donating, chromatic organic compounds selectedfrom the group consisting of diaryl phthalides, aryl phthalides,indolylphthalides, polyarylcarbinols, leucoauramines, acrylauramines,arylauramines, rhodamine B lactams, indolines, spiropyrans, fluorans,thiofluorans, phenothiazines, triphenylmethanes, diarylarylfurans,spiroxanthenearylfurans, and chromenoindoles, (b) one or more compoundscapable of reversibly accepting electrons of said organic compoundselected from the group consisting of phenolic hydroxy group-containingcompounds and derivatives thereof and carboxyl group-containingcompounds and derivatives thereof, (c) one or more compounds controllingthe temperature and sensitivity of coloration/decoloration of saidthermochromatic material selected from the group consisting of alcohols,esters, ketones, esters, acid amides and carboxylic acids, the ratio ofeach component to others (a):(b):(c) being 1:0.1 to 10:1 to 100 byweight, and (d) one or more radical cationic compounds selected from thegroup consisting of N-radical cationic, P-radical cationic, O-radicalcationic and S-radical cationic compounds having aromatic ring(s), in anamount of from 0.01 to 5 parts by weight per 1 part by weight of saidelectron-donating chromatic organic compound, said radical cationiccompound interacting with said electron-donating, chromatic organiccompound to stabilize said compound, resulting in a thermochromaticmaterial with an improved resistance to light.

In at least one embodiment, the color changing outer surface comprisesasphalt.

In at least one embodiment, a transparent layer is disposed over theouter surface.

In at least one embodiment, a roof comprises shingles having a colorchanging outer surface with a first color under a first environmentalcondition and a second color under a second environmental condition. Thecolor changing outer surface is capable of both changing from the firstcolor to the second color and from the second color to the first color.The shingles can be selected from the group consisting of asphalt, wood,metal, and/or concrete.

In at least one embodiment, the first environmental condition and thesecond environmental condition are selected from the group consisting oftemperature, light level, and any combination thereof.

In at least one embodiment, the color changing outer surface is coveredby a layer of transparent material.

In at least one embodiment, the outer surface comprises athermochromatic coating. In at least one embodiment, the outer layer isa laminate comprising thermochromatic material.

In at least one embodiment, the transition from the first color to thesecond color occurs at a threshold temperature. In at least oneembodiment, a gradual transition from the first color to the secondcolor occurs with a rise in temperature.

In at least one embodiment, the outer surface of shingles of asphalt,wood, metal, and/or concrete comprises (a) one or moreelectron-donating, chromatic organic compounds selected from the groupconsisting of diaryl phthalides, aryl phthalides, indolylphthalides,polyarylcarbinols, leucoauramines, acrylauramines, arylauramines,rhodamine B lactams, indolines, spiropyrans, fluorans, thiofluorans,phenothiazines, triphenylmethanes, diarylarylfurans,spiroxanthenearylfurans, and chromenoindoles, (b) one or more compoundscapable of reversibly accepting electrons of said organic compoundselected from the group consisting of phenolic hydroxy group-containingcompounds and derivatives thereof and carboxyl group-containingcompounds and derivatives thereof, (c) one or more compounds controllingthe temperature and sensitivity of coloration/decoloration of saidthermochromatic material selected from the group consisting of alcohols,esters, ketones, esters, acid amides and carboxylic acids, the ratio ofeach component to others (a):(b):(c) being 1:0.1 to 10:1 to 100 byweight, and (d) one or more radical cationic compounds selected from thegroup consisting of N-radical cationic, P-radical cationic, O-radicalcationic and S-radical cationic compounds having aromatic ring(s), in anamount of from 0.01 to 5 parts by weight per 1 part by weight of saidelectron-donating chromatic organic compound, said radical cationiccompound interacting with said electron-donating, chromatic organiccompound to stabilize said compound, resulting in a thermochromaticmaterial with an improved resistance to light.

In at least one embodiment, the outer surface is a coating, the coatingselected from the group consisting of powder coatings, paint, polymer,and any combination thereof.

In at least one embodiment, the coating is a powder coating selectedfrom the material group consisting of epoxies, polyesters, urethanes,nylon, vinyl, polyethylene, and any combination thereof.

In at least one embodiment, the outer surface coating is of uniformconstruction.

In at least one embodiment, at least one portion of the roof maintainsthe substantially same color under the first environmental condition andthe second environmental condition.

In at least one embodiment of the invention, a roof comprises an outersurface having a first color under a first environmental condition and asecond color under a second environmental condition. The outer surfacecan have the capability of both changing from the first color to thesecond color and from the second color to the first color.

In at least one embodiment, the first environmental condition isselected from the group consisting of temperature, light level, and anycombination thereof.

In at least one embodiment, the second environmental condition isselected from the group consisting of temperature, light level, and anycombination thereof.

In at least one embodiment, the outer surface comprises athermochromatic paint.

In at least one embodiment, the outer layer is a laminate comprisingthermochromatic material.

In at least one embodiment the first color is substantially darker thanthe second color (darker here assumes the same radiative/light source atthe same intensity on both colors). As an example, a first color isextant in cooler temperatures of between about −120 and 65 degreesFahrenheit, and the second color is extant in warmer temperatures ofbetween about 65 and 150. The darker color here can also include thecolor that absorbs more energy from the radiative source to which thesurface is exposed. Thus, for example, a monochromatic light sourcestriking a surface having that very same monochromatic color will absorbmore energy than a deeper hue of another color that is not. Thus, insome embodiments at a certain temperature/radiative intensity a roof canchange color to even a deeper hue of a different color in order tolessen the heating of a surface. While this would not generally be thecase when exposed to sunlight; in environments where a certain color oflight is used in a particular application it can be desirable

In at least one embodiment, the roof transitions abruptly from a firstcolor to a second color at a threshold temperature.

In at least one embodiment, the roof gradually transitions from thefirst color to the second color with a rise in temperature.

In at least one embodiment, the roof has roof panels that have an outersurface as described in the paragraph immediately above directlydisposed thereon.

In at least one embodiment, the outer surface is disposed on a membranedisposed on the roof panels.

These and other embodiments which characterize the invention are pointedout with particularity in the claims annexed hereto and forming a parthereof. However, for further understanding of the invention, itsadvantages and objectives obtained by its use, reference should be madeto the drawings which form a further part hereof and the accompanyingdescriptive matter, in which there is illustrated and describedembodiments of the invention.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

A detailed description of the invention is hereafter described withspecific reference being made to the drawing.

FIG. 1 is top view of a representative embodiment of the invention.

FIGS. 2 a-2 c are side cross-sectional views of an embodied roof.

DETAILED DESCRIPTION OF THE INVENTION

While this invention may be embodied in many different forms, there aredescribed in detail herein specific preferred embodiments of theinvention. This description is an exemplification of the principles ofthe invention and is not intended to limit the invention to theparticular embodiments illustrated. It should be noted that the terms“cooler temperature” and “warmer temperature” are relative. For example,in some embodiments the warmer temperature may be 32 degrees Fahrenheitwhile in other embodiments the cooler temperature may be 65 degreesFahrenheit. Generally, cooler temperatures may be between about −130 and75 degrees Fahrenheit and warmer temperatures may be between 10 and 200degrees Fahrenheit. These ranges are given primarily with regard topossible outdoor temperatures. In other embodied applications of thisinvention the ranges may be substantially colder than the cooltemperatures given and/or substantially hotter than the warmtemperatures given. Given the same environment and a color transitionthat occurs due to a change in temperature, the term “coolertemperature” is associated with a temperature cooler than thatassociated with the term “warmer temperature”.

It should be noted that the terms “lesser light intensity” and “greaterlight intensity” are relative to one another. For example, in someembodiments the greater light intensity on the surface may be 1.5 kW/m²or greater particularly if the surface is in manufactured light whilethe lesser light intensity is less than this. In other embodiments thegreater light intensity on the surface may be 0.75 kW/m² or greater; or0.25 kW/m² or greater. The lesser light intensity being less than thegreater light intensity in each embodiment and moving from the lesserlight intensity to the greater light intensity results in a change insurface coloration. Throughout the application the term thermochromaticshould be recognized to mean having a color at one temperature that isdifferent than the color at a different temperature. Unless heat andlight intensity are distinguished between, thermochromatic is also meantto include the meaning of having a color when exposed to one lightintensity that is different than the color at a different lightintensity. In some embodiments there are multiple color changesdepending on the characteristics of the thermochromatic properties ofthe surface with regard to temperature or light intensity. It should benoted that in other embodiments the greater light intensity can bebetween 1.5 and 10 kW/m². In some embodiments between about 10 and 100kW/m²; and in other embodiments between about 100 and 1000 kW/m².

In some embodiments it is desirable that the roof remain a darker hue inwarm temperatures such as on a cloudy day. In such an embodiment, thelight from the sun is not strongly reaching the roof thus the roof isnot heating up. For aesthetic reasons or for some other reason it can bedesirable for the roof to remain darker. Thus in some embodiments, thelight intensity must also reach a threshold intensity before the roofchanges color. And in some embodiments the light intensity alone cancreate a change of surface coloration.

For the purposes of this disclosure, like reference numerals in thefigures shall refer to like features unless otherwise indicated.

In FIG. 1 a top view portion of a representative roof 10 is shown. Inthis figure the roof has shingles 15. The shingles 15 can be madeentirely of a thermochromatic material. In other embodiments thethermochromatic material is applied to the shingles.

In FIG. 2 a the thermochromatic material is applied to multiple shingles15 as a coating 17 that extends over multiple shingles 15. Here theshingles are disposed on a roof substrate 20. The coating 17 could beapplied after the construction of the shingles 15 and/or after they areapplied to the roof substrate 20. In some embodiments the shingles arethemselves the substrate. The coating can be a fluid (e.g. paint),membrane, powder, prefabricated/postfabricated cover, or any combinationthereof that is applied to the shingles 15. The shingles can be of anysize that would be appropriate for roof construction. The length and/orwidth of the shingles can range from less than 4 inches to more than 100ft. In some embodiments the shingles 15 are fabricated as a sheetcomprising multiple shingles per sheet. In some embodiments the sheethas an actual overlapping of shingles wherein the shingles are boundtogether to form the sheet. In some embodiments the sheet is made toappear as if it comprises multiple shingles wherein it is actually ofsingle piece construction; in some embodiments sheets made to appear asif they comprise multiple shingles are formed together.

In some embodiments as in FIG. 2 b, each of the shingles 15 has its ownthermochromatic coating 17. The coating can be a fluid (e.g. paint),membrane, powder or any combination thereof that is applied to each ofthe shingles 15. The sizing of these shingles 15 can be as those in theparagraph above.

The coating 17 can be applied to roof systems including those ofasphalt, metal, membrane, slate, tile, stone, and/or plastic.

In FIG. 2 c the thermochromatic material 17 is part of the shingle 15itself. In this embodiment the thermochromatic coating is not applied toa shingle, but rather it is a part of the shingle composition itself.The thermochromatic material 17 can have a greater concentration on theexposed side of the shingle 15 than on the portion contacting thesubstrate 20.

Though the roof 10 in FIGS. 2 a-2 c illustrate the overlapping ofshingles 15, this overlap is not necessary. In some embodiments the roofhas no overlapping shingles 15. Moisture and/or sunlight passing intopossible cracks between shingles can be reduced by the sealing of thecracks between shingles 15 or by sizing the shingles such that thecracks are minimalized, or by sizing the shingles as one piece ofshingle covers the entire roof or at least a portion extending from thetop of the roof to the bottom of the roof. In instances where the roofis substantially flat an overlap need not exist though in someembodiments an overlap does exist. The roof 10 can have a base/substrate20 of one piece construction.

The thermochromatic coating 17 can also act to seal the roof as well. Insome embodiments the thermochromatic material is added to a sealant orpaint to form a continuous roof surface that seals cracks or spaces inthe substrate 20.

Dyes, paints, and/or inks having liquid crystals that aremicroencapsulated in the form of a suspension can be used as a part ofthe thermochromatic surface and/or the thermochromatic material of theshingles. After absorbing a certain amount of light or heat, thecrystallic or molecular structure of the pigment can reversibly changein such a way that it absorbs and emits light at a different wavelengththan at lower temperatures. This change in color can result fromselective reflection of certain wavelengths by the crystallic structureof the material, as it changes between the low-temperature crystallicphase, through anisotropic chiral or twisted nematic phase, to thehigh-temperature isotropic liquid phase.

During the twisted nematic phase the molecules can orient in layers withregularly changing orientation, which gives them periodic spacing. Thelight passing the crystal can undergo Bragg diffraction on these layers,and the wavelength with the greatest constructive interference can bereflected back, which is perceived as a spectral color. A change in thecrystal temperature can result in a change of spacing between the layersand therefore in the reflected wavelength. The color of thethermochromatic liquid crystal can therefore continuously range fromnon-reflective (black) through the spectral colors to black again,depending on the temperature. Though multiple liquid crystals can beused two examples are cholesteryl nonanoate and cyanobiphenyls.

After absorbing a certain amount of light or heat, the crystallic ormolecular structure of the pigment reversibly changes in such a way thatit absorbs and emits light at a different wavelength than at lowertemperatures.

It should be noted that the surfaces within this application can beeither interior or exterior. In cooler temperature a darker interiorfloor may be desirable as solar energy can heat the floor as well asreduce glare. In warmer temperature a lighter interior floor may bedesirable. Interior surfaces having exposure to the suns rays orartificial lighting may also benefit from a surface that changes colordue to temperature.

These energy saving roofs can also be formed on vehicles such as mobilehomes, pop-up trailers, trucks, tractors, golf carts, and cars. This canbe done in a similar way as with the more stationary roofs forbuildings. The thermochromatic material can be applied after generalconstruction as a paint or the like. The thermochromatic material canalso be constructed on the vehicle when manufactured. Thisthermochromatic material can also be used in tents, tarps and the like.Among other uses, this could be helpful on the farm or while camping.The materials can also be applied after initial manufacture.

The above disclosure is intended to be illustrative and not exhaustive.This description will suggest many variations and alternatives to one ofordinary skill in this art. The various elements shown in the individualfigures and described above may be combined or modified for combinationas desired. All these alternatives and variations are intended to beincluded within the scope of the claims where the term “comprising”means “including, but not limited to”.

Further, the particular features presented in the dependent claims canbe combined with each other in other mariners within the scope of theinvention such that the invention should be recognized as alsospecifically directed to other embodiments having any other possiblecombination of the features of the dependent claims. For instance, forpurposes of claim publication, any dependent claim which follows shouldbe taken as alternatively written in a multiple dependent form from allprior claims which possess all antecedents referenced in such dependentclaim if such multiple dependent format is an accepted format within thejurisdiction (e.g. each claim depending directly from claim 1 should bealternatively taken as depending from all previous claims). Injurisdictions where multiple dependent claim formats are restricted, thefollowing dependent claims should each be also taken as alternativelywritten in each singly dependent claim format which creates a dependencyfrom a prior antecedent-possessing claim other than the specific claimlisted in such dependent claim below.

This completes the description of the preferred and alternateembodiments of the invention. Those skilled in the art may recognizeother equivalents to the specific embodiment described herein whichequivalents are intended to be encompassed by the claims attachedhereto.

1. A roof comprising shingles, the shingles being of asphaltconstruction and having a color changing outer surface, the colorchanging outer surface having a first color under a first environmentalcondition and a second color under a second environmental condition, thecolor changing outer surface capable of both changing from the firstcolor to the second color and from the second color to the first color.2. The roof of claim 1 wherein the outer surface includes (a) one ormore electron-donating, chromatic organic compounds selected from thegroup consisting of diaryl phthalides, aryl phthalides,indolylphthalides, polyarylcarbinols, leucoauramines, acrylauramines,arylauramines, rhodamine B lactams, indolines, spiropyrans, fluorans,thiofluorans, phenothiazines, triphenylmethanes, diarylarylfurans,spiroxanthenearylfurans, and chromenoindoles, (b) one or more compoundscapable of reversibly accepting electrons of said organic compoundselected from the group consisting of phenolic hydroxy group-containingcompounds and derivatives thereof and carboxyl group-containingcompounds and derivatives thereof, (c) one or more compounds controllingthe temperature and sensitivity of coloration/decoloration of saidthermochromatic material selected from the group consisting of alcohols,esters, ketones, esters, acid amides and carboxylic acids, the ratio ofeach component to others (a):(b):(c) being 1:0.1 to 10:1 to 100 byweight, and (d) one or more radical cationic compounds selected from thegroup consisting of N-radical cationic, P-radical cationic, O-radicalcationic and S-radical cationic compounds having aromatic ring(s), in anamount of from 0.01 to 5 parts by weight per 1 part by weight of saidelectron-donating chromatic organic compound, said radical cationiccompound interacting with said electron-donating, chromatic organiccompound to stabilize said compound, resulting in a thermochromaticmaterial with an improved resistance to light.
 3. The roof of claim 2wherein the outer surface comprises asphalt.
 4. The roof of claim 1wherein a transparent layer is disposed over the outer surface.
 5. Aroof comprising shingles, the shingles having a color changing outersurface having a first color under a first environmental condition and asecond color under a second environmental condition, the color changingouter surface capable of both changing from the first color to thesecond color and from the second color to the first color, the shinglesbeing selected from the group consisting of asphalt, wood, metal, andconcrete.
 6. The roof of claim 5 wherein both the first environmentalcondition and the second environmental condition are selected from thegroup consisting of temperature, light level, and any combinationthereof.
 7. The roof of claim 5 wherein the color changing outer surfaceis covered by a layer of transparent material.
 8. The roof of claim 5wherein the outer surface comprises a thermochromatic coating.
 9. Theroof of claim 5 wherein the outer layer is a laminate comprisingthermochromatic material.
 10. The roof of claim 5 having a transitionfrom the first color to the second color that occurs at a thresholdtemperature.
 11. The roof of claim 5 having a gradual transition fromthe first color to the second color with a rise in temperature.
 12. Theroof of claim 5 wherein the outer surface comprises (a) one or moreelectron-donating, chromatic organic compounds selected from the groupconsisting of diaryl phthalides, aryl phthalides, indolylphthalides,polyarylcarbinols, leucoauramines, acrylauramines, arylauramines,rhodamine B lactams, indolines, spiropyrans, fluorans, thiofluorans,phenothiazines, triphenylmethanes, diarylarylfurans,spiroxanthenearylfurans, and chromenoindoles, (b) one or more compoundscapable of reversibly accepting electrons of said organic compoundselected from the group consisting of phenolic hydroxy group-containingcompounds and derivatives thereof and carboxyl group-containingcompounds and derivatives thereof, (c) one or more compounds controllingthe temperature and sensitivity of coloration/decoloration of saidthermochromatic material selected from the group consisting of alcohols,esters, ketones, esters, acid amides and carboxylic acids, the ratio ofeach component to others (a):(b):(c) being 1:0.1 to 10:1 to 100 byweight, and (d) one or more radical cationic compounds selected from thegroup consisting of N-radical cationic, P-radical cationic, O-radicalcationic and S-radical cationic compounds having aromatic ring(s), in anamount of from 0.01 to 5 parts by weight per 1 part by weight of saidelectron-donating chromatic organic compound, said radical cationiccompound interacting with said electron-donating, chromatic organiccompound to stabilize said compound, resulting in a thermochromaticmaterial with an improved resistance to light.
 13. The roof of claim 12wherein the outer surface is a coating, the coating selected from thegroup consisting of powder coatings, paint, polymer, and any combinationthereof.
 14. The roof of claim 13 wherein the coating is a powdercoating selected from the material group consisting of epoxies,polyesters, urethanes, nylon, vinyl, polyethylene, and any combinationthereof.
 15. The roof of claim 13 wherein the outer surface coating isof uniform construction.
 16. The roof of claim 5 wherein at least oneportion of the roof maintains the substantially same color under thefirst environmental condition and the second environmental condition.